University College London - MRC Clinical Trials Unit, University College London - MRC Clinical Trials Unit, University of the Witwatersrand - Perinatal HIV Research Unit, Department of Paediatrics, University of Zimbabwe, Baylor University - Children's Foundation Uganda, Joint Clinical Research Centre, Mbarara, Joint Clinical Research Centre, Mahasarakam Hospital, Makerere University - Johns Hopkins University Research Collaboration, University of the Witwatersrand - Department of Internal Medicine, University of KwaZulu-Natal, Stellenbosch University, Chulalongkorn University - Center of Excellence in Pediatric Infectious Diseases and Vaccines, University of Zimbabwe, Baylor University - Children's Foundation Uganda, Joint Clinical Research Centre, Chris Hani Baragwanath Academic Hospital, Goethe University, University Hospitals Birmingham NHS Foundation Trust, Research on AIDS and Viral Hepatitis (ANRS), University College London - Infection, Immunity and Inflammation Research & Teaching Department, Chiang Mai University, Makerere University - Johns Hopkins University Research Collaboration, Joint Clinical Research Centre, London School of Hygiene & Tropical Medicine - Department of Clinical Research, University of Padua - Department of Women’s and Children’s Health, University of Padua, University College London - MRC Clinical Trials Unit and University College London - MRC Clinical Trials Unit